Cementitious panels generally comprise a cementitious core material that contains a hydraulically setting material such as gypsum, cement, or the like, surrounded by a plurality of sheets of facing material such as paper or paperboard, or woven or non-woven fibers or filaments. The panels are typically manufactured using a continuous process, in which a slurry of cementitious core material is sandwiched between a lower and upper sheet of facing material. Typically the slurry of cementitious core material is applied on to a continuously advancing lower sheet of facing material, and a continuously advancing upper sheet of facing material is applied over the cementitious core material. The edges of the upper and lower sheets of facing material are adhered together using an adhesive. For example, the lower sheet of facing material may have long edges, which may be folded over the top of the gypsum slurry, with the long edges of the lower sheet underlapping the upper sheet of facing material. This process is sometimes referred to as “edge sealing” because the longitudinal edges or sides of the panel are, in a sense, “sealed” by the facing material. The slurry of cementitious core material and the sheets of facing material pass between parallel upper and lower forming plates or rolls, which shape a continuous length of cementitious panel material into a desired thickness and width. The panels are dried in an oven or kiln to evaporate excess (free) water. The dried panels may be further cut to desired sizes and bundled together for transfer to a warehouse or for shipping.
Certain materials can cause problems associated with adhering the sheets of facing material together, for example, in an edge sealing process. On the one hand, it may be desirable to utilize a relatively porous facing material, yet on the other hand, a porous facing material may allow adhesives to bleed through and onto the surface of the facing material. Adhesive on the surface of the facing material may come into contact with and accumulate on manufacturing equipment such as the forming plates or rolls, cutting equipment, conveyor belts or rollers, transfer table and lifting and lowering mechanisms, and the like. The buildup of adhesives on the manufacturing equipment can cause problems in operation of the equipment, and can increase process downtime required for cleanup and equipment maintenance. Additionally, adhesives that buildup on the manufacturing equipment can redeposit on the cementitious panels causing defects in panel quality.
Thus, it would be desirable to provide improved cementitious panels and improved systems and methods of manufacturing cementitious panels, for example, that minimize bleed through and accumulation of adhesives on the manufacturing equipment and redisposition of adhesives on the cementitious panels. The present disclosure addresses these needs by, among other things, providing cementitious panels that include a radiation-curable adhesive to adhere sheets of facing material to one another and by providing systems and methods for manufacturing such cementitious panels that include radiation-emitting devices to cure such radiation-curable adhesive.